Additional bedtime H2‐receptor antagonist for the control of nocturnal gastric acid breakthrough: A Cochrane systematic review

OBJECTIVES: To assess the effectiveness and safety of additional bedtime H₂‐receptor antagonists (H₂RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand‐searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H₂RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta‐analysis. There were no consistent conclusions found between the two included studies in evaluating H₂RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large‐scale randomized controlled trials with long‐term follow up are needed to determine the effects of additional bedtime H₂RAs in suppressing NAB.     

大鼠脑血肿周围组织半胱氨酸天冬氨酸蛋白酶3表达变化与尼莫地平的影响

目的：观察脑出血后血肿周围半胱氨酸天冬氨酸蛋白酶3的表达。及尼莫地平对其的影响。方法：实验于2004—07在大连医科大学中心实验室进行。取120只SD雄性大鼠随机分为3组：①尼莫地平组（n=50）：尾壳核注射自体股动脉血50μL复制脑出血模型，造模即刻腹腔注射尼莫地平1．6mg／kg（即8μL／g），以后每天1次。②模型组（n=50）：同前造模，术后腹腔注射等量生理盐水。③假手术组（n=20）：手术，但进针人尾壳核后不注血。各组分为术后6，24，48，72h、5d 5个时间点。造模动物醒后进行Bederson评分，评估其行为和神经功能缺陷（0—3分。评分越高，神经功能缺陷越重，评分≥2分为造模成功）。人组动物在以上5个时间点进行Bederson评分后，麻醉状态下处死取脑，经尾壳核行冠状切片，行免疫组化测定半胱氨酸天冬氨酸蛋白酶3表达。结果：80只大鼠进入结果分析。①Bederson评分：模型组、尼莫地平组大鼠醒后迅速出现偏瘫，24h后评分趋于稳定，至72h之间评分最高，然后逐渐下降，5d时仍有体征。模型组、尼莫地平组各时间点评分均高于对照组（P〈0．01），尼莫地平组术后48，72h评分低于模型组（P〈0.05）。②血肿周围组织半胱氨酸天冬氨酸蛋白酶3表达：假手术组进针侧脑组织表达很少，模型组6h后即有表达，24h达高峰，持续72h后逐渐下降，5d后仅有少量表达；尼莫地平组动态变化趋势与模型组相同，但各时间点的数值均较低，尤其是术后24～72h（P〈0．01）。结论：①脑出血后血肿周围组织中半胱氨酸天冬氨酸蛋白酶3表达升高，提示其与脑出血血肿周围组织损伤有一定关系。②尼莫地平降低脑出血后血肿周围组织中半胱氨酸天冬氨酸蛋白酶3表达，从而减轻细胞凋亡程度，对神经细胞起到保护作用，降低神经功能缺陷。     

60Co-γ射线全身低剂量率辐照对小鼠血浆中IL-12和IL-10的影响

目的研究低剂量电离辐射对小鼠免疫系统影响的剂量率效应。方法以^60Co-γ射线为辐照源，低、中和高3个辐射剂量（0．075、0．5、2．0Gy），恒定剂量率（0．5mGy／min）全身一次性照射小鼠，ELISA检测照射4h后血浆IL-12和IL-10的含量。结果低、中剂量照射后，血浆中IL-12、IL-10和IL-12／IL-10出现程度几乎相同地下降；但高剂量照射后，IL-12进一步显著下降，而IL-10上升至对照组水平，IL-12／IL-10比值进一步下降。结论恒定0．5mGy／min剂量率的^60Co-γ射线照射可损伤机体免疫功能，在0．075～0．5Gy剂量范围内损伤轻微，在2．0Gy时损伤明显，表明低剂量率电离辐射对免疫系统具有损伤作用。     

Long-term vardenafil therapy improves hemodynamics in patients with pulmonary hypertension.

The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.     

Risk factors and ankle brachial indexes in cerebral infarction combined with peripheral arterial disease

BACKGROUND: Ankle brachial index(ABI)is widely involved in researches and clinical application of peripheral vascular injury of patients with diabetes (DM);however ,the application in cerebral infarction(CI)is rare.OBJECTIVE: To investigate the possible risk factor of cerebral infarction plus peripheral arterial disease(PAD),compare metabolic characteristics of patients who having CI plus PAD or only having CI,and understand the significance of ABI on screening and diagnosing CI plus PAD of lower limb.DESIGN: Contrast observation based on CI patients.SETTING: Deparment of Neurology,Nanxishan Hospital of Guangxi Zhang Autonomous Region.PARTICIPANTS:A total of 124 CI patients were selected from Department of Neurology.Nanxishan Hospital of Guangxi Zhuang Autonomous Region from July 2005 to April 2006,including 72 males and 52 females aged from 45 to 88 years.All patients met the diagnostic criteria of cerebrovascular disease established by National Academic Conference of Cerebrovascular Diseases in 1995 and determined as cerebral infarction with MRI or CT examination.All patients provided informed consent.There were 46 cases(37.2%)with CI plus PAD and 78 cases(62.8%)only with CI.METHODS: Blood pressure of bilateral ankles and upper extremities was measured at plain clinostatism with DINAMAP blood pressure monitor(GE Company).The ratio between average systolic pressure of lateral ankle and average systolic pressure of both upper extremities was regarded as ABI.The normal ABI was equal to or more than 0.9.If ABI＜0.9 occurred at one side,patients were diagnosed as PAD.On the second morning after hospitalization,blood was collected to measure fasting blood glucose(FBG),2-hour postprandial blood glucose(PBG2h),glycosylated hemoglobin(HbAlc),triglycerides(TG),total cholesterol(TC),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C).Among them,blood glucose.lipid and other biochemical markers were measured with enzyme chemistry assay and HbA1c was measured with HbA1c meter based on high liquid phase.Measurement data and enumeration data were compared with t test and Chi-square test.and multiple factors were deat with Logistic regression analysis and multivariate linear regression analysis.MAIN OUTCOME MEASURES: Results of correlation between ABI and metabolic markers with multivariate linear regression analysis;risk factors of CI plus PAD with Logistic regression analysis;comparisons of metabolic markers between PAD and non-PAD patients.RESULTS:All 124 patients with acute CI were involved in the final analysis.①Comparisons of metabolic markers:Levels of serum LDL-C and uric acid(UA)were higher of PAD patients than those of non-PAD patients(t=2.051 9,3.339 1,P＜0.05);however,there were no significant differences among other metabolic markers(P＞0.05).②Results of multivariate linear regression analysis:PBG2h,LDL.C and UA were obvious correlation with ABI of posterior tibial artery of lower limb and dorsal pedis artery rpartial regression coefficient:-0.231 to-1.010,P＜0.05).③Risk factors of CI plus PAD with Logistic regression analysis:Age.Smoking history,sum of CI focus(≥3)and LDL-C were independent risk factor of CI plus PAD(OR=1.524-5.422,P＜0.05-0.01 ).CONCLUSION:①Levels of serum LDL-C and UA of patients with CI plus PAD are high.②ABI of lower limbs is correlation with PBG2h,LDL-C and UA.In addition,measuring ABI is beneficial for early diagnosing PAD of lower limbs of patients who have poorly controlled blood glucose,abnormal lipid and poor renal function.③Age,LDL-C and sum of CI focus(≥3)are independent risk factors of CI plus PAD.It is of significance for screening non-PAD patients to evaluate risk degrees and prognosis and select therapeutic methods based on ABI measurement.     

Olmesartan is an angiotensin II receptor blocker with an inhibitory effect on angiotensin-converting enzyme.

Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.     

颈肩背轴型反流皮瓣修复儿童颏颈瘢痕挛缩

目的探讨修复儿童颏颈瘢痕挛缩一种实用而较理想的方法.方法以颈横动脉浅支为蒂,利用其与旋肩胛动脉皮支的丰富吻合,反流形成超长的轴型皮瓣,向前旋转修复瘢痕松解后的颈前创面.结果采用本皮瓣修复30例儿童颏颈瘢痕挛缩,其中18例随访2年,颈部活动自如,颌骨发育无明显异常,皮瓣色泽良好,效果令人满意.结论本皮瓣轴型血管恒定,反流灌注动脉压高有保证,供瓣面积充足,供区多可直接拉拢缝合,是修复儿童颏颈瘢痕挛缩的较理想方法.     

网络环境下医学专题检索服务的深化

分析网络环境下图书馆定题服务的现状和价值，提出跟踪服务的方式，进行分阶段的、具体的定题服务，并实例分析分阶段定题服务的优势。     

骨髓间充质干细胞分化为皮肤附属器细胞的初步实验研究

目的探讨骨髓间充质干细胞(marrowmesenchymalstemcells,MSCs)分化为创面皮肤附属器细胞的可能性,及其参与创面修复的可能机制。方法无菌条件下取Wistar大鼠股骨骨髓细胞,密度梯度离心分离、纯化MSCs,体外培养扩增后,用BrdU标记细胞。另于同种雄性Wistar大鼠背部正中,制备1cm×1cm全厚皮肤缺损创面模型,将BrdU标记的1×106/mlMSCs从阴茎静脉输注,术后第3天与第7天切取创面组织,行BrdU免疫组织化学单染色,以及BrdU和广谱角蛋白免疫组织化学双染色。结果BrdU阳性细胞出现在创面皮下组织、皮脂腺、毛囊和骨髓腔中。免疫组织化学双染色结果显示,皮脂腺和毛囊有BrdU阳性细胞,同时表达广谱角蛋白。结论创面愈合过程中,MSCs归巢并参与创面修复;在实验性全身皮肤缺损创面微环境下,MSCs可分化为皮肤附属器细胞。     

结节病肺部改变的CT征象分析

目的探讨结节病肺部改变的CT表现及特征。方法回顾性分析90例经手术病理证实的结节病的临床资料及CT表现。结果结节69例（76．7％），主要沿支气管血管束分布37例（41．1％），团块影31例（34．4％），磨玻璃影39例（43．3％），支气管血管束增粗30例（33．3％），小叶间隔线58例（64．4％），纤维化17例（18．9％），包括支气管变形8例（8．9％）、条索影5例（5．6％）、蜂窝影4例（4．4％），空气潴留3例（3．3％），支气管狭窄8例（8．9％），胸膜改变42例（46．7％），肺门纵隔淋巴结增大76例（84．4％）。2种及2种以上肺部病变并存83例（92．2％），肺部病变合并肺门纵隔淋巴结增大76例（84．4％）。结节、团块、磨玻璃影、支气管血管束增粗治疗后随访吸收好转例数分别为25例（25／30）、9例（9／15）、11例（11／16），10例（10／12）；小叶间隔线、支气管变形、条索影、蜂窝影吸收好转例数分别为10例（10／22）、0例（0／4）、1例（1／3），0例（0／2）。结论结节病肺部CT表现形式多样，具有一定特征性，同时结合肺门纵隔淋巴结增大改变，有助于提高诊断正确率。